Telephone system



Jan..- 29, 1929. 1,700,469 R. D. CONWAY TELEPHONE SYSTEM Filed May 16, 1924 2 Sheets-Sheet 1 l Wye/77W -i Ray 0. Cam/0y by A1734 Jan. 29, 1929.

R. D. CONWAY TELEPHONE SYSTEM Filed may 16, 1924 ZSheets-Sheet 2 wwwk a.

Patented Jan. 29, 1929.

entree s'rArss PATET FFICE.

ROY D. CONWAY, OF BASKING RIDGE, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TELEPHONE SYSTEM.

Application filed May 16, 1924. Serial No. 713,698.

My invention relates to improvements in telephone exchange systems and especially to that class employing automatic switching mechanism for extending connections to and from subscribers lines, trunks or switch boards controlled by operators.

The main object of this invention is to intercept conections to lines, trunks, or switch boards, to route the connectionthus intercepted to an intercepting operator at some distant central point, and to indicate to her the reason why the line or trunk with which connection has been established is not available for use.

Connections to lines may be intercepted in order to give special service to lines which are out of order, or to notify the calling party that the called line has been disconnected, is temporarily out of service, or that its number has been changed; connections to unused or dead trunks are likewise intercepted and transferred in order to prevent the calling party, who in such cases has dialed the wrong number, from being inconvenienced.

In order to intercept such connections, the lines or trunks are cross-connected or wired to terminals of an automatic switch which when operated extends such connections to the intercepting operators desk.

The wiring or cross-connections to the terminals includes conductors connected to currents having special characteristics. The intercepting desk is provided with equipment which responds to such currents and which in turn operates signals indicating to the operator the class to whichthe intercepted lines or trunks belong, or in other words,the reason why the called line or trunk is not available for use.

My invention is illustrated in the flCCOHk" panying drawings wherein:

Fig. 1 shows the intercepting trunk equipmcr; located at an ottlce containingautomatic switchingmechanisin. Theswitchingmechanism at XX comprises selector and connector switches or the Strowger type illustrated and described in patents to Keith and Erickson Nos. 815,321 and 815,176. In the present instance I have shown these switches in 21 diagrammatic manner. The finder switch for V aiding the connection from the selector or (.(1111100101 switches as the case may be is of the type known as the Keith line finder switch.

The details oi. this sw tch including the plunger mechanism is not shown.

tending a connection from selector levels from subscribers lines.

Fig. 2 shows the equipment located at the exchange containing the operators intercepting desk. Relays CC, DD and EE have their windings in series and are operated in certain combinations depending upon what character of current is connected to their windings throu h the operation of the finder switch Fig. 1. The cooperation 01 these relays controls the operation of relays X, Y, Z, which in turn control the-operation of the signal lamps XL, YL and ZL, these lamps serve when lighted to indicate to the operator the class to which the-intercepted trunk or line belongs. The details of this circuit will be pointed out in the description to follow. 7

In describing the operation of my system, I will first describe in detail how a connection from toll selector levels is intercepted and extended to the operators intercepting desk or position, when the toll selector has encountered a dead trunk in which case the lamp 800 will be connected to the positive pole of a 110 volt battery whose negative pole is' grounded.

In the present instance the operators cord circuit, supervisory relay and dial are not shown in detail. It is within common knowledge that tell cord circuits are provided with a relay having its winding connected in bridge across the talking conductors, which controls the extinguishing of the ordinary supervisory lamp.

When the toll operator manipulates the dial associated with her cord circuit and operates the switch 200, ground is connected to the sleeve side of the trunk operating relay CO which locks through its windings in series and causes the plunger of the finder switch, to'operate the bank contacts 600 automatically connecting the cord circuit to a trunk er:- tending to the intercepting operators position.

After this connection is made relay A is operated by a positive current supplied by the llO-volt battery in series with the lamp 300 through the contacts of the plunger switch. The operation of relay A in turn completes the circuit of relay B. At the time the plungor is operated relay AB is operated in circuit with the l8-volt battery in series with the winding oi relays E and F as follows ground L8-volt battery, winding of relay AB, contacts of plunger switch, 2, 54, windings oi relays E and F, contacts of relay GG, 24t-volt battery to ground. Relay E which is polarized operates, but relay F which is marginal does not due to the high resistance of the winding of relay AB in series with it.

The operation of relay B connects or extends the circuit from the 110-volt battery as follows:

Positive llO-volt battery, 500, lamp 300, contacts of plunger switch, contacts of relay B, 3, contacts of relay N, i, 5, winding of relay AA, 6, contacts of relay Z, 7, contacts of relay Y, 8, contacts of relay X, 9, winding oi relay U, 1.0, winding of relay BE, 11, Wind ing of relay DD, 12, winding of relay CC, to ground. The current passing through this circuit operates relays AA, U, EE, DD, and CC.

The operation of relay All causes the operation of relays FF and BB as follows:

Ground, contacts of relay AA, 13, winding of relay FF, 14, contacts of relay S, 15, contacts of operators listening key, 16, winding of relay BB, 17 to battery and to ground. Belay FF operated locks in series with relay RE.

The operation of relay U completes the circuit of relay V as follows: ground, winding of relay V, 21, 20, 19, contacts of relay BB, 17, to battery.

The operation of relays EE and CC by the 1l0-volt positive current completes the circuit out relay X as follows: ground, con tacts of relayv CC, 22, contacts of relay ICE, 23, contacts of relay V, 24, inake-betore-break contacts and winding of relay X, 18, contacts of relay BB, 17, to battery. Relay X operates and locks under control of relay BB.

The operation of relay X disconnects the tip of the trunk from the winding of relay U and bridges relays AA and W across the tip and ring of the trunk. Relay 0, Fig. 1 now operates as follows: ground, contacts of relay B, 67, ll, winding of relay O, 40, contacts of relay R, 39, 38, contacts of relay winding of relay W, contacts of relays K, Y and Z, winding of relay AA, 5, 4, contacts of relay N, 3, contacts or relay B, contacts of plunger switch 600, lamp 300, 500 to 110 volt battery. Relays W and Q now operate.

The operation .of relay also opens the circuit extending through the windings of relays U, EE, DD and CC. The ll relay restoring, releases relay V which discomiccts the common selecting circuit from relays X, Y and Z.

The operation of relay E operates the relay D as follows: battery, contacts of relay D, 68, contacts of relay E, 43, winding of relay D, 44, contacts of relay A to ground. The operation of relay D completes the circuits ct relay H as follows: ground, contacts of relay L, 45, contacts of relay D, 46, winding of relay l-l, 4-7, contacts 01 relay HH, battery to ground. The operation of relay H connects battery and ground through the windings of relay J to the tip and ring of the line. Relay J and relay TS in the toll cord now operate inseries the latter closing a signalling circuit not shown to furnish the toll operator with. a ringing signal,

The operation of relay D also completes the circuit or relay JJ as follows: ground, contacts of relay D, 52, contacts of relay GG, 30, winding of relay JJ, battery to ground. Relaydd is slow to operate in order to allow relay J to operate and in turn operate relay C before relay operates under control of relay JJ as hereinafter described. The operation of relay all completes the circuit of relay GG as follows: ground, contacts of relay JJ, 55, make-betore-break contacts and winding of relay GG, battery to ground. Re lay GG operated locks under control or" relay A. The operation of relay GG opens the circuit through relays E and F which are in series by removing battery from the winding of relay F, and also opens the operating circult of relay JJ releasing relays E, F, and JJ.

The operation of relay J connects ground to the winding of relay C which in turn opcrates and connects ground by way of 2 to the winding of relay AB, thus providing a circuit to keep relay AB operated after relay GG operates and opens the originalopcrating circuit of relay AB. 'Relay C, which is designed to be slow release, does not release when the toll operator rings on the line or in case she should attempt to manipulate the dial.

The resistances and 51 are variable and their value depends upon the length or resistance of the toll switching trunks used with the toll selectors.

When the toll operator rings, the alternating current operates relay P, which is bridged across the tip and ring conductors. The oper ation of relay P completes the circuit of relay Q and this relay in operating in turn operates relay R as follows: ground, contacts of relay 0, 59, contacts of relay Q, 60, winding of relay R, battery to ground. Relay is designed to be slow to release, so that it does not vibrate its armature in uniscnwith that of relay P, thus maintaining the operating circuit of relay it closed to insure the proper operation of the latter relay, and to prevent relay N from being operated prematurely. Relay R operated locks itself to ground through the contacts of relay B. The operation of relay R opens the circuits ofrelays O, W and Ali, causing them to release.

Relay W releasing lights the lamp XL, thus giving a distinguishing signal to the intercepting operator. When the toll operator discontinues ringing, relay P releases and in turn releases relay Q. Relay Q, releasing causes the operation'of relay N as follows: ground, battery, winding of relay N, 62, contacts of relay Q, 60, 7 5, contacts of relay R, 67, contacts of relay B to ground.

The operation of relay N connects the talking circuit through from the trunk to the intercepting operator and connects relay M and L in series across the tip and ring of the trunk which is extended to the intercepting operator.

The operator noticing the lighting of the lamp XL operates the listening key which opens'the circuit through relays FF and BB releasing relay FF. Relay BB remains operated over a circuit to ground at the make contacts of the listening key.

The operation of the listening key also completes the circuit of relay S as follows: ground, winding of relay S, 64, contacts of listening key, 19, contacts of relay BB, battery to ground.

Belay S in operating looks over the above circuit to battery through the contacts of relay BB.

The operation of relay S connects ground and battery through the windings of relay T and through the contacts or the flashing key to the tip and ring of the trunk in such a direction that when the flashing key is in its normal position relay M which'is polarized does not operate but relays L and T are operated. The operationof relay T disconnects ground from the lamp XL thereby extinguishing it. The operation of relay T also connects ground to the winding of relay BB maintaining it energized after the listening key is restored.

The operation of relay L opens the circuit of relay H and connects ground to the Winding of relay C through the contacts or relay D to prevent relay C from releasing when relay J releases. Relay H in releasing disconnects the windings of relay J from the tip and ring or the intercepting trunk, thereby removing ground and battery current from the winding of the supervisory relay in the toll operators cord circuit causing the supervisory signal associated therewith to become extinguished.

It the intercepting operator wishes toflash or signal the toll operator, the flashing key isoperated which reversesthe battery'supply to the intercepting trunk thereby causing the operation of polarized relay M. The operation of relay M operates relay H as follows: ground, contacts of relay M, 76', contacts of relay Gr, 80, 77, contacts of relay D, 16, winding of relay'H, 47, contacts of relay HH to battery.- The operation of relay H connects battery through the windings of relay J to the line extending to the toll operator, causing the operation of both relay J and the supervisory relay in the cord circuit at the toll operators position. The

release immediately, but remains operated long enough for relay J to close a substitute holding path which prevents it from releasing. When the flashing key is restored, relay M releases, releasing relay H which opens the circuit through the windings of relay J which releases. relay G, by way of the make contact of relays L and D and the break contact or relay H, is again closed thus preventing relay C from releasing after relay J releases.

When the intercepting operator rest-ores the listening key the direction or current flow in the tip and ring conductors of the trunk is reversed operating the polarized relay M The holding circuit. for

which operates the relay H in the'manner I previously described. The operation of re lay I-I opens the holding circuit for relay C. If the toll operator is still connected to the trunk, relay J will reoperate and prevent relay C from releasing and under these circumstances relay T remains operated in series with the bridge formed by the windings of relays L and M across the trunk circuit and the lamp XL will relight over the following circuit: ground, contacts of relay T, normal contacts of the listening key, 15, contacts of relay S, lamp XL, contacts of relay X, contacts oi relay BB, battery, to ground. The lighting of lamp XL will indicate to the intercepting operator that the toll operator is still connected to the trunk and she will accordingly reoperate the listening key and resume the conversation.

If the toll operator disconnects before the listening key is again operated at the intercepting position relay J will release, releasing relay 0. The release of relay 0 opens the circuit through relay AB which likewise releases, releasing relay CO. The release of relay CO separates the bank contacts 600 thus opening the circuit through the winding of relay A which releases in turn releasing relays B, D'and GG. The release of relay B releases relays N and R. The release of relays N and R opens the bridge through the Winding of relays M and L from across the trunk circuit releasing relays M, L and T. The release of relay T eXt-inguishes the including the calling station.

is denied service in which case the lamp 300 will be connected tothe negative pole of a 110 volt battery, whose positive pole is grounded.

The bank contacts or terminals of the plunger switch are wired as shown at 700. Instead of having the winding of relay AB connect ground to the sleeve of the trunk, ground is placed thereon through the wipers of the selector switch. This ground connection serves to operate the relay BOO. In operating, the relay BCO operates the plunger switch, thus extending the ground supplied by the switch wipers to relays E and F whose windings in series. Relay E which is polarized does not operate due to the direction of the current flow in its winding. The direction of the flow of current in the winding of relay E is now opposite to that of the flow which occurred when relay E was placed in series with the winding of relay AB to the 48 volt battery. The marginal relay F is operated instead. Relay A is operated by the 110 volt battery tive current) in series with the'larnp 300, and operates relay B in the manner previously described. The operation of relays A and F completes the circuit of relay G as follows: ground, contacts of relay A, -44, 7i, winding of relay G, 70, contacts of relay l contacts of relay E, 42, to battery through the contacts of relay D. The operation of relay G connects ground and battery through the winding of relay K to the tip and ring of the trunk through the normally closed contacts of relay H which is not operated at this time. Relay K now operates in series with loop The operation of relay K connects ground to the sleeve of the trunk to provide a holding circuit for the various selector switches in the train of switches which extend the calling line to the intercepting trunk.

The operation of relay B connects the 110- volt battery to the windings of relays AA, U, EE, DD and CC as described in connection with the extension from a toll selector level.

Relays AA, U, DD and CC will operate as The operationott relay iiidescribed before. causes the operation of relays FF and BB,

while relay U causes the operation of relay V,

DD and CC. Relay U releasing restores ,re-'

lay V disconnecting the selecting circuit from relays X, Y and Z.

"When relay K is operated in the manner previously described, it completed the-circuit of relay R as follows: ground, contacts of ductor 67 and the contacts of relay B. The.

groundsupplied by relay B maintains both relays R andN operated. Theoperation of relays R and N bridges relays L and M in. series across the-trunk.

It relays R and N 1) operate before relay Z (Fig. 2), relay WV will not operate, but if relay Z operates-before relays N and R, relay W Will operate momentarily in series with relay 0 (Fig. 1), over a circuit includingthe llO-voltbattery. In either case when relay VJ is normal and relay Z is locked, lamp ZL lights under control of relays T, W, Z and BB. VJ hen relay R opera-ted, ground was connected to the windings of relays G and GG as follows: ground, contacts oiirelay HH,- 73, contacts of relay K, 74,- contacts of relayR, 57, windings oi? relays C and GG. The operation of relay 0 maintains ground on the sleeve conductor in case the subscriber should operate his dial causing the relay Klto vibrate. Relay GG locks to ground through the con tacts of relay A. The operation oi; relay GG.

opens the circuit through the windings of're:

lays E and F in series, releasing relay F. Relay G remains looked under control of relay A.

When the intercepting operator answers the call and operates the listening key, relay S operates, openingthe: bridge through relays AA and W and connecting battery through the windings of relay .T to relays L and M in series, operating relay L. Relay K releases when the subscriber replaces his receiver, releasing relay C which removesground from the sleeve of the trunk, releasing relay ECO. The intercepting line finder switch 700 will restore, allowingall of the re lays to release and restore the circuits to normal.

If the intercepting operator restores the listening key before the calling subscriber replaces the receiver on'the switchhook, the

battery reversal caused-by restoring the listening key to normalwill operate the polarized relay M. The operation of relay M closes the followingcircnit to operate relay 'H: ground, contacts of relay M, 76, contacts,

of relays Gr, 81, 46, winding of relay H, 47, contacts of relay HH, battery, to ground; The operation of relay H substitutes the windings of'relay J for those of relay K across the tip and ring of the. intercepting circuit. So long as the calling subscriber remains on the circuit, relay J will operate, preventing relay C from releasing. Relay T (Fig. 2) will remain operated in series with relays L and M, relighting the lamp ZL over the following circuit: ground, contacts of relay T, normal contacts of the listening key, 15, contacts of relay S, 69, lamp ZL, contacts of relay Z, contacts of relay BB, battery, to ground. The intercepting operator may now operate the listening key to resume the conversation, thus extinguishing lamp ZL. If the calling subscriber replaces the receiver before the intercepting operator reoperates the listening key, relay J will release, releasing relay C. The release of relay C removes ground from the sleeve of the trunk circuit, releasing relay BOO, thus separating the bank contacts 700 and opening the circuit through the winding of relay A which releases. The release of relay A releases relay B, which in turn, releases relays N and B. The release of relays N and B releases relays L, M and T. The release of relay T extinguishes the lamp ZL and re leases relay BB. Relay BB releases relays Z and S, restoring the circuit to normal.

When a toll operator calls through a connector and the connection is to be intercepted, conductor 2, extending from the sleeve side of the trunk through the terminals of the line switch bank 600, is omitted from the circuit. By omitting this conductor, relays E, F, C and D are not operated in the manner described when a connection is extended by the toll operator through a selector only.

Relays A, B, U, AA, EE, DD, CC, X, V, FF, BB, W and O are operated in the manner described when the connection was extended by the toll operator through a selector only.

When the connector switch is connected to the intercepting trunk, automatic ringing is started in the connector switch and ringing current is connected to the intercepting trunk operating relay P, which is bridged across the tip and ring conductors. The operation of relay P completes the circuit of relay Q. The operation of relay Q completes the circuit of relay B as follows: ground, contacts of relay 0, 59, contacts of relay Q, 60, winding of relay R to battery. This relay B when operated locks itself to ground through the contacts of relay B. The operation of relay B opens the circuit of relay 0 and connects ground by way of the contacts of relays B, R, Q and O to the ring of the intercepting trunk thereby extending the ground connection to the connector switch preventing further application of ringing current. ring of the trunk only so long as relay Q, remains energized. This relay is slow to release and remains operated for a short pe riod after relay I? releases due to the This ground is connected to the ing current being discontinued, to insure the removal of the ringing current from the circuit.

When relay Q releases, relay N is operated as follows: ground, contacts of relay B, 67, contacts of relay R, 7 5, 60, contacts of relay Q, 62, winding of relay N to battery. Relay N operating completes the talking circuit from the connector to the intercepting operator and connects relays M and L across the tip and ring conductors.

When relay R was operated disconnecting relay 0 from the ring of the trunk, it caused the release of relay W which in restoring completes the circuit of the lamp XL causing it to light.

The intercepting operator answering,

operates the listening key connecting holding ground to the winding of relay BB and releasing FF relay as before and causes the operation of relay S which looks itself to battery through the contacts of relay BB. The windings of relay T (Fig. 2) and relays L and M (Fig. 1) are connected in series as previously described operating relays Tand L. The operation of relay T opens the circuit of lamp XL which is extinguished and closes a circuit to maintain relay BB energized. The operation of relay L operates relay H which connects battery supply through the windings of relay J to the tip and ring of the intercepting trunk causing the operation of the toll operators supervisory signal. The battery supply from the toll operators switching trunk is such that battery from the trunk meets ground connection through the winding of relay J, while ground from the trunk meets battery through the other winding of relay J. Belay J operating completes the circuit of relays C and GG. Relay C as before stated is slightly slower in operating than relay GG, so that it does not have time to operate before relay GG opens the circuits of relays F and E to prevent their operating.

If the intercepting operator wishes to flash the toll operator, the flashing key is operated which reverses battery supply on the intercepting trunk operating relay M. This relay in operating completes the circuit of relay HH, which releases relay H and connects ground and battery to the tip and ring of the intercepting trunk through the windings of relay K, releasing the supervisory relay of the toll trunk circuit, due to the fact that the battery supply from the toll trunk circuit, and the intercepting trunk circuit oppose each other. Relay C which is slow to release will remain operated during this series of momentary substitutions of relay K for relay J.

When the toll operator disconnects, then the finder switch and all the relays of the interceptin trunk will be restored to normal as previously described.

In case a subscriber or an operator calls through a connector and the connection is'eX- tended the operation will be the same as when the toll operator calls through a connector e cepting that when relay H operates connecting battery and ground to the intercepting trunk through the windings of relay J the latter relay does not operate as the battery supply from the connector is connected to the battery supply winding of relay J while the ground connection from the connector is connected to ground through the other winding of relay J.

The intercepting operator may desire to recall a local operator in which case the flashing key is operated reversing battery on the trunk. Relay is operated which in turn operates relay HH, which in turn releases relay H connecting battery and ground through the windings of relay K to the tip and ring of the intercepting trunk. Battery is connected in such a manner that the back release relay of the connector is operated causing the supervisory lamp in the local operators cord circuit to light. The release operation of the connection is the same as when the call originates through toll selector levels.

When a subscribers line circuit is taken from service on account of trouble on the line, it is connected to an intercepting circuit. In such a case the intercepting circuit is sup plied with negative ail-volt battery instead of the llO-volt battery and lamp 300, and when the line switch plunges, relay A operates in series with 4.8-volt battery, operating relay B and connecting 4L8-volt battery over the trunk line to the intercepting circuit, thence by way of 4c, 5, the winding of relay AA, 6, contacts of relay Z, 7 contacts of relay Y, 8, contacts of relay X, 9, winding of relay U, 10, winding of relay EE, 11, winding of relay DD, 12, winding of relay CC, to ground. Relays AA, U and CC, operate. Relay EE which is polarized is not responsive to negative current supplied over the tip of the trunk, hence, it does not operate at this time. Relay DD is marginal and is designed to operate on 110- volt current connected to the tip of the trunk. but not to operate when lS-volt current is connected to the tip of the trunk, hence, relay DD does not operate at this time. Relays BB and FF operate and lock in series as previously described. Belay V operates under control of relay U as previously described. A circuit is now closed to operate relay Y as follows: ground, contacts of relay CC, 22, contacts of relay E13,?! ,contacts of relay DD,

28, contacts of relay V, 29, contacts and winding of relay Y, 18, contacts of relay BB battery, to ground. Relay Y operates and locks under control of relay BB and the lamp YL lights under control of relays BB, Y, 7 and T. The circuit functions from this point in the same general manner as previously described.

The lamps XL, YL and ZL are character- .ized by distinctive markings so that when lamp XL lights, the intercepting operator knows immediately that the calling party or 1. In a telephone exchange system, calling lines and classified called lines, automatic switches for interconnecting Calling and called lines, an operators position with sigals thereat, means wherebythe automatic switches are connected to said operators position in lieu of a called line, and means controlled by the automatic switches for automatically operating said signals to indicate the classification or" the called for line.

2. In a telephone exchange system, calling I lines and various types of called lines, automatic switching mechanism for interconnecting calling and called lines, an 'operatorsposition with signals thereat, means for automati- .:ally intercepting the connection for the called line and extending it to said operators position, and means after such a connection is extended to operate said signals to indicate the type of the called for line.

3. in a telephone exchange system, calling lines and classified called lines, automatic switching mechanism for interconnecting said lines, an operators position provided with signals and controlling relays thercat, said relays being selectively responsive to currents of different characteristics, and means for automatically intercepting the connections torthe called lines and to extend them to said position, the extension of said connections causing said currents to operate certain of said relays, the operation of said relays serving to operate certain of said signals to display the classification of the called for lines.

a. In a telephone exchange system, lines, selector and. connector switches for extendconnections to said lines, means for classifying said lines, an automatic switch, an operatoi"s position with signals thcreat, means for further extending said lines via said automatic switch to said position, and means for operating said signals for indicating the classification of said extended lines.

5. In a telephone exchange system, a plurality of groups of classified called circuits, an operators position with signals thereat, means to automatically extendrsaid circuits to said position and to operate said signals to indicate the classification of the extended circuits.

6. In a telephone exchange system, trunks, lines, means for selecting said trunks and lines, automatic switching mechanism at a central ofice for extending trunks and lines, said trunks and lines being classified,an intercepting operators desk located at an office separate from said central ofiice and provided with signals, and means including said switching mechanism for extending said trunks and lines to said desk and to operate said signals to indicate the classification of said lines and trunks.

7. In a telephone exchange system, trunks, lines, means for selecting said trunks and lines, automatic switching mechanism at a central oflice for extending said trunks and lines, means at said office for intercepting the connection to said trunks and lines, and an intercepting operators desk having signals thereat, said signals responsive when said lines or trunks are intercepted to indicate the class to which they belong.

8. In a telephone exchange system, a plurality of groups of called circuits, a series of automatic switches for extending said cir cuits, means for classifying said circuits and said switches, an operators position provided with signals, means for intercepting said circuits and any switch in the series and for extending them to said position, and means for causing the operation of said signals when said circuits are intercepted to indicate the classified switch or circuit so intercepted.

9. In a telephone exchange system, a plurality of classified called circuits, a series of antomatic switches for extending said circuits, means for automatically intercepting said circuits, an operators position provided with a plurality of relays, and means controlled by said. intercepting means for connecting said circuits to said relays for causing their operation in accordance with the classification of said circuits.

10. In a telephone exchange system, a plurality of called circuits, automatic switches for interconnecting said circuits, an automatic finder switch for intercepting said circuits, a plurality of different sources of current supply, means for associating said sources with and for classifying said circuits, an operators position having relays and signals thereat, means controlled by the operation of said finder switch for extending the sources of current supply and circuits to said position to operate the relays and said signals to indicate the class of circuits extended.

11. In a telephone exchange system, a plurality of called circuits, automatic switching mechanism for extendin connections from and to said circuits, a p urality of different sources of current supply associated with said circuits, each source of current supply indieating a certain class to which said circuits belong, an operators position provided with relays and signals, said relays responsive to said sources of current supply, an automatic finder switch interposed between said circuits and said position, means controlled by the operation of said finder switch to extend said circuits and sources of current supply to said position, the connection of said sources of current supply to said relays causing their operation, the operation of said relays causing the operation of said lamps to indicate the class of circuits extended to said position.

12. In a telephone exchange system, a plurality of called circuits, a difierent source of current supply associated with each of said circuits to classify them, automatic switches for interconnecting said circuits, an operators position provided with signals thereat, an automatic finder switch for extending connections from said circuits to said position, the extension of said sources of current supply associated with said circuits serving to operate said signals to indicate the class to which the extended circuits belong.

13. In a telephone exchange system, a plurality of called circuits, a plurality of different sources of current supply arranged to be associated with said circuits to classify them, an operators position with relays and signals thereat, an automatic switch for extending said circuits and sources of current supply to said position to operate said relays, the operation of said relays causing the operation of said signals to indicate the class of circuits extended.

1%. In a telephone exchange system, a plurality of classified called circuits, an operators position with signals thereat, an automatic switch, means controlled by the operation of said automatic switch for extending said circuits to said position, the extension of said circuits serving to operate said signals to indicate the classification of said circuits.

15. I11 a telephone exchange system, a plurality of classified called circuits, means for extending said circuits,'a switch for inter cepting the extension of said circuits, an operators position with signals thereat, the operation of said switch when intercepting the extension of said circuits serving to transfer them to said position to operate said signals to indicate the class of circuits transferred.

16. In a telephone exchange system, a plurality of classified called circuits, an operators position provided with a plurality of relays in series relation, said relays being responsive to currents of different characteristics, means for classifying said circuits by associating therewith currents of different characteristics, an automatic switch, means to automatically operate said switch to extend said circuits and associated sources of cur rent supply to said position to operate said relays, the operation of said relays serving to operate said signals to indicate the class oi circuits extended.

17. In a telephone exchange system, calling lines, and classified called lines, means for extending connections between said lines, an operators position With signals thereat, means for automatically extending said lines to said position in lieu of called lines and means to operate said signals to indicate the classification of the called lines. v

18. In a signaling system, a plurality of controllable devices, means for remotely con trolling any one of said devices, automatic n eans for selecting an idle one of said controllable devices and establishing an interconnection between said device and said controlling means whereby said device is set in accordance with a routing provided by said controlling means, a plurality of signals for indicating when the device aforesaid is set With respect to any one of them, and means for operating the particular signal aii'ected to indicate a routing.

19. In a signaling system, a plurality of operable devices, means for remotely controlling any one 01" said devices, automatic means for selecting an idle one oi said operable devices and establishing an interconnection between said device and said controlling means whereby said device is operated, a plurality of signals each indicating a diiierent setting of the device aforesaid to indicate diiferent routings, and means for operating some one of the signals to indicate a particular routing.

In witness whereof, I hereunto subscribe my name this 15th day of May, A. D. 1924 ROY D. GONWAY.

DISOLAI MER 1,700,469.R0g 1). 00mm? Basking Ridge, N. J. TELEPHONE SYSTEM. Patent dated January 29, 1929. Disclaimer filed July 13, 1931, by the assignee, Western Electric Company, lncorpotatecl.v

Hereby enters this disclaimer to the said claims of said Letters Patent which are in the following Words to wit:

2. In a telephone exchange system calling lines and various types of called lines, automatic switching mechanism for interconnecting calling and called lines, an operators position with signals thereat, means for automatically intercepting the connection for the called line and'extending it to said operators position, and means after such a connection is extended to operate said signals to indicate the type of the called for line.

17. In a telephone exchange system, calling lines and classified called lines, means for extending connections between said lines, an operators position with signals thereat, means for automatically extending said lines to said position in lieu of called lines and means to operate said signals to indicate the classification of the called lines.

[Ofitcial Gazette August 11, 1.931.] 

